The present invention relates to compression dosage units, such as tablets, and more particularly relates to low density dosage units formed by compressing tabletting feedstock material.
Dosage units in the form of tablets are prepared by compressing a formulation containing a medicinal substance or drug and other ingredients, such as excipients selected for properties which enhance the production and use of the tablet. There are currently three known basic methods for preparing tablet granulations. These are wet granulation, dry granulation and direct compression. Both wet and dry granulations involve the formation of an agglomerate for feeding to a die cavity. Direct compression usually involves compressing a powder blend of an active ingredient with suitable excipients.
Other methods of preparing feedstock for preparing compression dosage units have been disclosed in copending, commonly owned U.S. application Ser. No. 08/194,682 filed Feb. 10, 1994, U.S. application 08/259,996, pending, and filed on Jun. 14, 1994, and U.S. application Ser. No. 08/259,258, pending, also filed Jun. 14, 1994. Each of these applications are incorporated herein by reference.
U.S. application No. 08/194,682, pending, discloses a method of making a solid comestible by compressing shearform matrix masses sufficiently to form a comestible compression unit. U.S. application No. 08/259,496, pending, discloses a method of preparing a quick dissolve comestible unit by mixing uncured shearform matrix and an additive, molding a unit dosage form therefrom, and curing the shearform matrix. Finally, U.S. application Ser. No. 08/259,258, pending, discloses a method of preparing quick dissolve comestible units by initiating crystallization of shearform matrix, and combining, either before or after initiating crystallization, an additive with the shearform matrix to form flowable, compactible micro-particulates. Finally, the micro-particulate medium is compacted to form the quick dissolve comestible unit. In each of these disclosures, the tabletting medium is prepared initially by use of shearform matrix. In most cases a quick dissolve tablet can be produced by providing a compressed body which is low density and capable of being disintegrated and dispersed relatively rapidly, and in many cases, instantaneously.
Tabletting processes known today in the art generally include the use of a machine which includes opposing punches and cavities into which a tabletting medium can be directed and subjected to compression between the punches. See, for example, U.S. Pat. No. 4,943,227, U.S. Pat. No. 4,880,373, U.S. Pat. No. 2,214,505, U.S. Pat. No. 2,068,619. Other references which discloses different shapes of dosage units are U.S. Pat. No. 4,493,822, U.S. Pat. No. 4,376,111, and an excerpt from The Consumer Guide for "Prescription Drugs," p. 194-208, Publications International, Ltd. (1990). None of the references cited above, however, show or suggest how to provide a low density dosage unit which has enhanced commercial value because of sufficient strength to be manufactured, disseminated, and sold in the appropriate commercial setting.
It is, therefore, an object of the present invention to overcome difficulties normally associated with low density compression units. Other objectives will also be apparent in view of the disclosure set forth herein.